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[sceptre74]

It chewed through a fair bit of wood yesterday. I have it set at 195 with a 10 degree dif and sometimes it would dip down to 175. It would only idle for maybe 10 minutes at a time. The return got to 80 last night and I shut it down because the temp inside was at 55 and I'm away from the house for the day so not there to feed it. Outside temps are at 65 today but back down to the 30's tonight. I'll get it going again tomorrow and see how it goes from there

[sceptre74]

So it's been a couple of weeks since I've been up and running and my delta really hasn't changed. I dropped my supply to 100 and the the return temp at startup is around 60 and never gets much above 80. I do have to say that there isn't a call for heat too often either. Maybe twice a day at the most so far. I'm assuming this is why the return temp is so low at start up. Do any of you see any issues in my future?

[sceptre74]

Figured I'd add a pic of my setup incase I did something wrong.



(picture posting corrected by Sloppy.  )

[Sprinter]

So it's been a couple of weeks since I've been up and running and my delta really hasn't changed. I dropped my supply to 100 and the the return temp at startup is around 60 and never gets much above 80. I do have to say that there isn't a call for heat too often either. Maybe twice a day at the most so far. I'm assuming this is why the return temp is so low at start up. Do any of you see any issues in my future?

Sounds good, but u might have lag time on colder or windy days. It looks like the mixing valve is your limiting/choking factor. Find out what it's flow rate is......meaning I have replaced many of those due to lack of heat problems. They forget that they can only flow so many GPM before the head loss skyrockets. An the circ can't move anymore, even tho the circ will flow way more at lower HL.  If it takes more than 6 hours for return temp to be within 10-20' of supply,and air temp is a problem,  that's where u look. Good luck, looks nice

[sceptre74]

Thanks sprinter. Without the help of members here I'd still be scratching my head. Lol. I'll check to see if I can find the flow rates on it. I seen another post you commented on that you used ball valves to maximize flow and still get the desired temp. I just may have to go that route if it becomes a problem

[sceptre74]

I've been keeping an eye on my delta with the infloor and the best I've seen it get to is 36. So this is what I'm thinking of doing. All 6 loops in the floor have water flowing the same direction. Would it help or make any difference of I were to change the flow of 3 of them in the opposite direction? Loops 1 3 and 5 flowing the same way and loops 2 4 and 6 the opposite direction. Thanks

[atvalaska]

1/2 gallon a minute is fast enough!!!  any faster and the heat don't get a chance to deliver !! ..  heat the "perimeter" 1st   try for a D-T of 20 degs ! ....110 degs is what my 4way/w/outdoor reset, is feeding  my floor rite now ..and its 30 below out !!

[sceptre74]

Chatting with another member last night and he figures my pump isn't quite big enough. I'm sending it at about 1 gpm. Gonna try a bigger one to see if it tightens that number up. Thanks

[atvalaska]

I have 2000' of muilt core 1/2" pex  on the same pump  u have ...just saying..

[LittleJohn]

Chatting with another member last night and he figures my pump isn't quite big enough. I'm sending it at about 1 gpm. Gonna try a bigger one to see if it tightens that number up. Thanks

1 GPM is plenty fast, like ATVALASKA -> don't sorry so much about GPM, focus more on your Delta T.  As long as your delta T is less than 20f, you should be in the ball park. 
My dad is running 14 loops of 1/2" - 300's off of an Alpha and each loop is seeing about 1/2 to 3/4 of a GPM, with no complaints of house being cold

[sceptre74]

If I don't increase the gpm's how will I get my delta T lower? A return of 82 is the highest I've seen it so far.
The building is plenty warm but I'm worried about straining the boiler. I spoke with Robert at P & M and suggested I install a diverted valve to send supply water to mix with the return after it leaves the return side of the floor. Hopefully this will make it easier on the owb

[LittleJohn]

If I don't increase the gpm's how will I get my delta T lower? A return of 82 is the highest I've seen it so far...

When you say return of 82, do you mean at the manifold or on the OWB side of the FPHE??
C

• If only the manifold return temp is 82, I would not worry too much
• If the water coming out of the Return side of the FPHE is 80, then I would get concerned
• What are the temperatrures on all 4 ports of the FPHE, after about 5 minute of the start of a call for heat??

...as long as the water going back to the OWB is at or above 140f, you should not see any long term issues (before 140f condensation can occur in the reaction chamber and lead to RUST -> and welding).  May need to turn up the pump between the OWB and the FPHE.

[sceptre74]

It's the return on the manifold that is 82 degrees. The return on the owb side of the hx usually doesn't go any lower than 165. When the boiler shuts back off at the 195 set point the return is around 175 to 180

[LittleJohn]

It's the return on the manifold that is 82 degrees. The return on the owb side of the hx usually doesn't go any lower than 165. When the boiler shuts back off at the 195 set point the return is around 175 to 180

Ok, glad you are not putting you boiler at risk, by having return water too low.   

Now I see no real problem with the Return manifold being at 82, but what is the approximate temperature of your Supply Manifold?   ALSO, as long as the wife and OWB are both happy and working, GREAT JOB 
If its much above 105 or so I would either; turn up your pump and see if delta T drops, or depending on where your Mixing Valve is set turn it up and see if that also brings up the return temps.

If the Delta T across the 2 manifolds is at or around 20f that is good; you can run with larger delta t's but beware you may get following HOT/COLD spots in the slab and/or heat stripping, and is generally not recommmend. 

[sceptre74]

The supply is at 110 and the pump us oh high already. I might still pick up a 26-99 to see if a little more flow tightens it up. I'm also figuring the diverter valve will restrict the flow somewhat so it might be necessary.